NUREG- 1552, Supp. 1 Fire Barrier Penetration Seals in Nuclear Power Plants U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation AVAILABILITY NOTICE Availability of Reference Materials Cited in NRC Publications NRC publications in the NUREG series, NRC regu- NRC Public Document Room lations, and Title 10, Energy, of the Code of Federal 2121 L Street, N.W., Lower Level Regulations, may be purchased from one of the fol- Washington, DC 20555-0001 lowing sources: <http://www.nrc.gov/NRC/PDR/pdrl.htm> 1-800-397-4209 or locally 202-634-3273 1. The Superintendent of Documents U.S. Government Printing Office Microfiche of most NRC documents made publicly available since January 1981 may be found in the RO. Box 37082 Washington, DC 20402-9328 Local Public Document Rooms (LPDRs) located in <http://www.access.gpo.gov/sudocs> the vicinity of nuclear power plants. The locations 202-512-1800 of the LPDRs may be obtained from the PDR (see previous paragraph) or through: 2. The National Technical Information Service <http://www.nrc.gov/NRC/NUREGSI Springfield, VA 22161-0002 SR1350N9/lpdr/html> <http://www.ntis.gov/ordernow> 703-487-4650 Publicly released documents include, to name a few, NUREG-series reports; Federal Register no- The NUREG series comprises (1) technical and ad- tices; applicant, licensee, and vendor documents ministrative reports, including those prepared for and correspondence; NRC correspondence and international agreements, (2) brochures, (3) pro- internal memoranda; bulletins and information no- ceedings of conferences and workshops, (4) adju- tices; inspection and investigation reports; licens- dications and other issuances of the Commission ee event reports; and Commission papers and and Atomic Safety and Licensing Boards, and their attachments. (5) books. Documents available from public and special tech- nical libraries include all open literature items, such A single copy of each NRC draft report is available as books, journal articles, and transactions, Feder- free, to the extent of supply, upon written request al Register notices, Federal and State legislation, as follows: and congressional reports. Such documents as theses, dissertations, foreign reports and transla- Address: Office of the Chief Information Officer tions, and non-NRC conference proceedings may Reproduction and Distribution be purchased from their sponsoring organization. Services Section U. S. Nuclear Regulatory Commission Copies of industry codes and standards used in a Washington, DC 20555-0001 substantive manner in the NRC regulatory process E-mail: <[email protected]> are maintained at the NRC Library, Two White Flint Facsimile: 301-415-2289 North, 11545 Rockville Pike, Rockville, MD 20852-2738. These standards are available in the library for reference use by the public. A portion of NRC regulatory and technical informa- Codes and tion is available at NRC's World Wide Web site: standards are usually copyrighted and may be purchased from the originating organization or, if they are American National Standards, from- <http://www.nrc.gov> American National Standards Institute All NRC documents released to the public are avail- 11 West 42nd Street able for inspection or copying for a fee, in paper, New York, NY 10036-8002 microfiche, or, In some cases, diskette, from the < http://www.ansi.org > Public Document Room (PDR): 212-642-4900 NUREG-1552, Supp. 1 Fire Barrier Penetration Seals in Nuclear Power Plants Manuscript Completed: December 1998 Date Published: January 1999 C. S. Bajwa, K. S. West Division of Systems Safety Analysis Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ABSTRACT In NUREG-1552, "Fire Barrier Penetration Seals in systems and components within an area from a fire Nuclear Power Plants," the U.S. Nuclear Regulatory outside the area. For the reasons given in this report, Commission staff documented the results of its it is the staff's judgment that, generically, typical comprehensive technical assessment of penetration penetration seal deficiencies do not equate to a lack seals. Subsequently, the staff assessed new of adequate protection or result in undue risk to information for new insights. The results of the public health and safety. It is the staff's opinion that updated assessment are documented in this report. continued licensee attention to existingpenetration Nuclear power plants use the "defense in depth" seal programs and continued NRC reviews and concept of echelons of fire protection to achieve a inspections are adequate to (1) provide reasonable high degree of fire safety. Fire barrier penetration assurance that penetration seal problems are seals, which are one element of the fire protection discovered and resolved and (2) maintain public defense-in-depth concept, are designed to confine a health and safety. fire to the area in which it started or to protect plant iii iiiNUREG-1552, Supp. I TABLE OF CONTENTS Page A B STR A CT ................................................................................ iii EXECUTIVE SUM M ARY ................................................................... vii DEFENSE-IN-DEPTH CONCEPT AND THE ROLE OF PENETRATION SEALS ................ I 1.1 Assessments of Fire Barrier Penetration Seals .......................................... 1 1.2 The Role of Penetration Seals in the Defense-in-Depth Concept ........................... 1 2 REVIEW OF REACTOR OPERATING EXPERIENCE ...................................... 3 2.1 Licensee Event Reports ........................................................... 3 2.2 NR C Inspections ................................................................ 4 2.3 Fire Experience ................................................................. 5 2.4 Summary of Operating Experience .................................................. 6 3 SAFETY SIGNIFICANCE ............................................................. 6 3.1 Fire Protection Program ............................................................ 6 3.2 Safety Significance Ranking of Penetration Seal Deficiencies ............................. 7 3.3 Generic Assessment of Safety Significance ............................................ 7 3.3.1 Improperly Installed or Degraded Seals and Inadequate Documentation ................ 8 3.3.2 Unsealed and Breached Penetrations ........................................... 9 3.4 Seal-Specific Assessment of Safety Significance ....................................... 10 4 RISK SIGNIFICANCE ............................................................... I I 5 COMPENSATORY MEASURES ...................................................... 11 6 PLANT-SPECIFIC EXPERIENCE WITH FIRE BARRIER PENETRATION SEALS ............. 11 6.1 Vermont Yankee Nuclear Power Station ............................................. 11 6.2 W olf Creek Nuclear Generating Station ............................................. 12 6.2.1 Operating Experience ...................................................... 12 6.2.2 01 Investigation ........................................................... 12 6.3 Salem Nuclear Generating Station .................................................. 13 6.4 M illstone Nuclear Power Station ................................................... 13 6.5 M aine Yankee Atomic Power Plant ................................................. 13 6.5.1 NR C Inspection ........................................................... 13 6.5.2 Licensee Event Reports .................................................... 14 6.5.3 Staff Follow up ............................................................ 14 6.5.4 Conclusions on Maine Yankee Operating Experience ............................. 15 6.6 C onclusions ................................................................... 15 7 REVIEW OF PLANT-SPECIFIC LICENSING BASES RELATED TO SECTION III.M OF APPENDIX R TO 10 CFR PART 50 ................................................. 15 7.1 Introduction ................................................................... 15 7.2 Plant-Specific Licensing Bases .................................................... 16 7.2.1 Calvert Cliffs Nuclear Power Plant, Units 1 and 2 ............................ 16 7.2.2 Duane Arnold Energy Center ............................................ 16 7.2.3 James A. FitzPatrick Nuclear Power Plant .................................. 17 7.2.4 Maine Yankee Atomic Power Plant ....................................... 17 7.2.5 Monticello Nuclear Generating Plant ...................................... 17 7.2.6 Peach Bottom Atomic Power Station, Units 1 and 2 ........................... 17 7.2.7 Pilgrim Nuclear Power Station, Unit I ..................................... 17 v NUREG-1552, Supp. 1 Table of Contents Page 7.2.8 Point Beach Nuclear Plant, Units I and 2 ................................... 18 7.2.9 H.B. Robinson Steam Electric Plant, Unit 2 ................................. 18 7.2.10 Surry Power Station, Units 1 and 2 ........................................ 18 7.2.11 Vermont Yankee Nuclear Power Station ................................... 18 7.3 Sum mary ..................................................................... 19 8 RECOMMENDATIONS IN THE FINAL STAFF REPORT ................................. 19 8.1 Introduction ................................................................... 19 8.2 Status ........................................................................ 19 8.2.1 Recommendations 1, 2, and 3 (Pending) .................................... 19 8.2.2 Recommendation 4 (Complete) ..........................................